Implantation Which of the following sequences correctly describes prenatal development? A. blastocyst implants in uterus, zygote
forms, heart begins beating, lungs can breathe air, sex organs become visible B. blastocyst implants in the uterus, zygote forms, heart begins beating, sex organs become visible, lungs can breathe air C. zygote forms, blastocyst implants in the uterus, heart begins beating, sex organs become visible, lungs can breathe air D. zygote forms, blastocyst implants in the uterus, sex organs become visible, heart begins beating, lungs can breathe air 3. Which of the following correrti
The bronchus in the lungs are lined with hair-like projections called cilia that move microbes and debris up and out of the airways. Scattered throughout the cilia are goblet cells that secrete mucus which helps protect the lining of the bronchus and trap microorganisms.